Spinal disorders such as degenerative disc disease, disc herniation, osteoporosis, spondylolisthesis, stenosis, scoliosis and other curvature abnormalities, kyphosis, tumor, and fracture may result from factors including trauma, disease and degenerative conditions caused by injury and aging. Spinal disorders typically result in symptoms including pain, nerve damage, and partial or complete loss of mobility.
Non-surgical treatments, such as medication, rehabilitation and exercise can be effective, however, may fail to relieve the symptoms associated with these disorders. Surgical treatments of these spinal disorders include discectomy, laminectomy, fusion and implantable prosthetics. During surgical treatment, one or more rods may be attached via fasteners, e.g., bone anchors, to the exterior of two or more vertebral members to provide stability to a treated region. However, the fasteners must be placed such that they are sufficiently spaced apart from neural elements to avoid pain. However, placement of fasteners is largely done blindly, and even in the hands of experienced surgeons, the incidence of misplaced fasteners resulting in neurological impairment can be quite high despite the use of surgical inspection and imaging techniques. This disclosure describes an improvement over these prior art technologies.)